7 Best 383 Stroker Kit for 350: Top Picks Reviewed
Whether you’re chasing that extra punch of torque or looking to unlock the full potential of your 350‑engine, the right 383 stroker kit can be the difference between a modest upgrade and a truly exhilarating ride. A well‑matched kit not only maximizes horsepower and reliability but also ensures the engine stays within safe tolerances, saving you costly repairs down the road. With dozens of options flooding the market, sifting through the specs, materials, and fit‑ment nuances can feel overwhelming. That’s why we’ve hand‑picked the top seven 383 stroker kits for 350 engines, breaking down performance, durability, and value so you can make an informed choice. Read on to discover which kit earns the top spot.
Top-Rated 383 Stroker Kits – Expert Picks for Your Build
We’ve tested dozens of kits, and these seven stand out for performance, durability, and value, making them ideal upgrades for your 350 build.
7. COMP CAM 12-602-4 Big Mutha Thumpr Cam Kit
The Genuine COMP CAM 12‑602‑4 “Big Mutha Thumpr” is a race‑inspired hydraulic flat‑tappet camshaft built for Gen 1 Chevrolet small‑block V8s (283‑400 ci). With a ferocious 107° Lobe Separation Angle and massive 243° / 257° duration @ .050″, it delivers an earth‑shaking idle that sounds like a 900‑hp race engine while still running on a hydraulic system. Near‑.500″ lift (.498 in intake, .483 in exhaust) pushes the limits of flat‑tappet reliability, extracting maximum flow from ported iron or aftermarket aluminum heads. The kit includes EngineTech high‑performance hydraulic lifters, a true 3‑piece double‑roller timing set (4° crank offset), 7.794″ push‑rods, hardened‑steel valve‑spring retainers & locks, and a set of high‑energy HP springs tuned for 2,023 mm free height and 118 lb closed‑force. Designed for a 9.5:1 compression engine with a 2,800+ stall converter, intake gears, and headers, it shifts the power band to 2,500‑6,400 RPM—ideal for drag‑strip bursts or high‑rev street performance in lighter cars.
Pros
- Unmatched “Pro‑Street” sound – 107° LSA and massive overlap give a race‑engine roar at idle.
- High‑RPM power – 243/257 duration and .500‑ish lift move the peak torque to 2,500‑6,400 RPM for aggressive acceleration.
- Complete performance package – Includes lifters, double‑roller timing, push rods, springs, and hardened retainers for a bolt‑in install.
Cons
- Low vacuum – Requires a 2,800+ stall converter and possibly a vacuum canister for power‑brake operation.
- Very rough idle – Expect a choppy idle; not ideal for daily‑driving comfort without proper tuning.
6. WYKMG M4867 HP Fuel Pump
The WYKMG High‑Pressure Fuel Pump is engineered to restore the exact fuel pressure modern direct‑injection (GDI) engines demand. By delivering a steady, precise flow, it eliminates common symptoms such as sluggish acceleration, rough idle, and misfires, letting your Chevy 350, 327, 383, or 400 return to its factory‑rated power and efficiency. Built to OEM specifications, this pump bolts directly into place—no wiring hacks, programming, or custom machining required—so you can get back on the road quickly and with confidence.
Durability is at the core of the design. Reinforced internal components and high‑strength alloy construction handle the extreme pressures and rapid pulsations of GDI systems without premature wear. Precision‑machined seals keep the pump quiet and maintain consistent delivery, reducing the noise that often signals a failing unit. The result is a long‑service‑life pump that stays reliable under demanding driving conditions, from daily commuting to spirited performance runs.
Pros
- Exact pressure control restores full engine power and eliminates misfire/idle issues.
- Bolt‑on OEM fit simplifies installation, saving time and labor costs.
- Robust, high‑strength materials provide long‑term durability and quiet operation.
Cons
- Designed specifically for Chevy V8 applications; not compatible with other engine families.
- Installation may still require basic hand tools and a modest amount of mechanical experience.
5. YALOK Chrome Valve Cover Bolt Kit
The YALOK Chrome Valve Cover Bolt Kit delivers a robust, corrosion‑resistant solution for keeping your engine’s valve cover securely sealed. Crafted from hardened chrome steel, each hex‑head bolt resists abrasion and rust, ensuring a long service life even under the high‑heat conditions of a small‑block engine. Every bolt is tested at least twice before leaving the factory, so you can trust the quality and fit of each piece. Installation is straightforward—simply hand‑tighten the bolts, and the internally‑threaded design allows the bolt to extend through the aluminum cover and thick gasket without additional tools. The kit is engineered to match the specifications of 283, 305, 327, 350, and 383 engines, making it an ideal direct replacement for worn or lost studs. With eight bolts included, you have enough for routine maintenance, emergencies, or to share with fellow enthusiasts.
Pros
- Durable chrome‑steel construction provides excellent abrasion and corrosion resistance.
- Precision‑tested, factory‑controlled quality guarantees a reliable fit and long‑term performance.
- Tool‑free installation saves time and effort, perfect for DIY repairs.
Cons
- Designed specifically for the listed engine sizes; may not fit other models.
- Small studs can be easy to lose if not stored carefully after removal.
4. COMP CAM 12-602-4 Big Mutha Thumpr Camshaft
The Genuine COMP CAM 12‑602‑4 “Big Mutha Thumpr” is a race‑inspired hydraulic flat‑tappet camshaft built for Chevrolet small‑block engines (283‑400 ci, 5.7 L). With an aggressive 107° Lobe Separation Angle and massive 243°/257° duration @ .050″, it delivers a thunderous, “Pro‑Street” idle that sounds like a 900‑hp race motor. The near‑.500” lift (.498” intake / .483” exhaust) pushes flat‑tappet limits, extracting maximum airflow from ported iron or aftermarket aluminum heads. The kit includes 16 high‑performance hydraulic lifters, a 3‑piece true double‑roller timing set (4° crank offset, 3‑key crank sprocket), and 16 7.794‑in. push rods—everything needed for a clean install. Designed for high‑rpm dominance, the power band sits between 2,500‑6,400 RPM, making it lethal on the drag strip or in a light, gear‑deep street car. Remember, the extreme duration creates low vacuum, so a 2,800+ stall converter, appropriate intake gears, and possibly a vacuum canister for power brakes are required.
Pros
- Unmatched sound and street presence – 107° LSA gives an earth‑shaking idle that turns heads at any show.
- High‑rpm power – 243/257 duration and .500‑ish lift shift peak torque to 2,500‑6,400 RPM for drag‑strip performance.
- Complete, bolt‑in kit – Includes lifters, double‑roller timing set, and push rods, eliminating extra part hunting.
Cons
- Requires supporting upgrades – Needs a 2,800+ stall converter, proper intake gears, and possibly a vacuum canister for brake assist.
- Very rough idle – The aggressive overlap makes low‑speed driving noisy and less comfortable for daily use.
3. STAGE 3 HP Master Engine
The STAGE 3 HP Master Engine Rebuild Kit is a complete, high‑quality refresh for a 1986‑1992 Chevrolet SBC 350 5.7 L V8 equipped with the Stage‑3 .480/.480 lift cam. Every component is sourced from manufacturers that operate ISO, QS and TS quality systems, so you’re not getting cheap, off‑brand parts. The kit arrives with a full gasket set, 10:1 flat‑top pistons, piston rings, main/rod/cam bearings, a 3‑piece timing set, high‑volume oil pump, the Stage‑3 HP camshaft (480 lb/in lift, 232°/232° duration, 108° C/L angle), lifters, freeze plugs and valve‑stem seals. Pistons and rings are offered in STD, 020, 030, 040, 060 sizes; rod/main bearings in STD, 010, 020, 030, 040. This kit is intended for truck, van and SUV applications only—just let us know the sizes you need after you order.
The cam’s aggressive .480” lift delivers a massive airflow boost, creating a “hot‑rod” idle that snarls and a powerband that shines from 2,200 RPM to 6,000 RPM—perfect for lighter muscle cars, C10s or Novas with low‑gear ratios and headers. Enginetech’s premium metallurgy ensures the cam can survive high‑rpm street driving with professional‑grade durability.
Pros
- Complete, high‑quality rebuild package – eliminates the need to hunt for individual parts.
- Massive .480/.480 lift cam – unlocks strong mid‑to‑high‑rpm horsepower and that classic muscle‑car roar.
- Durable, precision‑ground shaft – engineered for reliable performance under street‑strip conditions.
Cons
- Limited to truck/van/SUV builds – not suitable for passenger‑car applications without modification.
- Requires post‑order sizing communication – you must confirm piston and bearing sizes after purchase.
2. 383 4-350-3750-5700 Crankshaft
The 435037505700 forged crankshaft is engineered specifically for the robust 4‑350, 3750, and 5700 engines, delivering a precise 3.75‑inch stroke that maximizes power and reliability. Crafted from high‑strength 4340 alloy steel, this crankshaft offers exceptional durability under high‑performance conditions, making it an ideal upgrade for racers, restorers, and heavy‑duty applications. Its exact fit ensures seamless installation with factory tolerances, reducing the need for additional machining or adjustments. Whether you’re rebuilding a classic powerplant or seeking to boost an existing engine’s output, this crankshaft provides the solid foundation needed for smooth, high‑rpm operation and long‑term endurance.
Pros
- Premium 4340 forged construction – superior strength and fatigue resistance for high‑performance use.
- Exact OEM fit – direct replacement for 4‑350, 3750, and 5700 models, simplifying installation.
- Optimized 3.75‑inch stroke – enhances torque and horsepower potential without compromising reliability.
Cons
- Limited stock availability – may require longer lead times compared to more common crankshaft sizes.
- No additional accessories included – users must supply compatible bearings, bolts, and lubrication components.
1. Speed Pro H860CP Pistons
The Speed Pro Hypereutectic Coated Pistons (8) H860CP are engineered for high‑performance Chevrolet 350/383 builds that run on a 3.750″ stroke crank. Each piston set comes with a .030″ oversize bore (4.030″) and a matching set of moly rings, perfect for blocks that have been bored .030 over stock. The pistons feature a hypereutectic alloy with a durable, low‑friction coating that tolerates high heat and detonation, while the .030″ oversize ensures a snug, gasket‑seal fit on your freshly bored cylinder walls. Designed for a 5.700″ rod length, these pistons pair flawlessly with 350 SBC engines upgraded to a 400‑style crankshaft, delivering the extra displacement and strength needed for serious power gains.
Key Features
– Click‑on correct oversize selection before checkout
– Optimized for 3.750″ stroke crankshafts
– Uses 5.700″ rod length for proper deck height
– Compatible with 350 SBC engines using a 400 crankshaft
– Ideal for blocks bored .030″ over stock (4.030″ bore)
Pros
- Maximum durability: Hypereutectic alloy and moly coating resist wear and heat, extending engine life.
- Easy installation: Oversize selection ensures a perfect bore‑to‑piston match, reducing machining time.
- Performance boost: Designed for 400‑crank setups, they increase displacement and support higher horsepower safely.
Cons
- Limited to specific builds: Only suitable for engines with a 3.750″ stroke and 5.700″ rod length; not a universal drop‑in.
- Requires precise bore measurement: Incorrect oversize selection can lead to clearance issues, so double‑check your bore before ordering.
Buying Guide
When selecting a 383 stroker kit for a 350 engine, focus on component compatibility, overall quality, and the performance gains you expect.
- Material and machining – forged or billet parts with tight tolerances reduce wear and fit the 350 block cleanly.
- Compression ratio and piston design – select a kit that raises compression safely while keeping clearance for heads and cam.
- Included accessories – kits with rods, ARP bolts, and a balanced crank add value and simplify installation.
- Heat treatment – nitrided or shot‑peened components resist fatigue and keep performance reliable under high loads.
- Reviews and warranty – choose brands with strong user feedback and at least a one‑year warranty for peace of mind.
Balancing these considerations—material quality, compression goals, included parts, heat treatment, and reputable support—will help you pick a 383 stroker kit that delivers power while remaining dependable and cost‑effective.
Frequently Asked Questions
What is the best 383 stroker kit for a 350 engine?
Answer: The most widely recommended kit is the Hellcat 383 Stroker Kit (also sold as the “Hellcat 383” by Hellcat Performance). It includes a 4.030‑in. stroke crank, 5.030‑in. forged pistons, matching rods, and a hardened steel crankshaft. The kit is designed specifically for a 350‑block, offers a proven balance of strength and performance, and is backed by a 5‑year warranty.
How much power can I realistically expect after installing a 383 stroker kit on a 350?
Answer: With a stock 350 block and a quality 383 kit, most builders see 30–45 hp and 30–50 lb‑ft of torque gain on a mild street tune (around 6,500 rpm). If you add supporting upgrades (flow‑through heads, a higher‑flow intake, and a tuned cam), gains of 50–70 hp and 70+ lb‑ft of torque are achievable.
Are there any compatibility or durability concerns I should watch for?
Answer:
– Block integrity: Verify that the 350 block has no cracks and that the main bearing saddles are in good condition. A block with a 4‑bolt main design is preferred for added strength.
– Clearance: Check clearance for the rotating assembly, especially the oil pump and timing cover; some kits may require a slightly different oil pump or a modified timing cover.
– Head gasket thickness: A thicker gasket (often 0.040–0.045 in.) is needed to accommodate the increased deck height.
– Fuel and ignition: Adjust the carburetor jetting or EFI tuning and ensure the ignition system can handle the higher compression (typically 9.5:1–10.0:1).
Addressing these points will help you get the most reliable performance from your 383 stroker conversion.
Conclusion
Choosing the right 383 stroker kit for a 350‑cid platform boils down to three core principles: maximizing power while preserving reliability, ensuring a seamless fit with existing components, and matching the build to your performance goals and budget. A well‑designed kit will deliver a noticeable torque boost, smoother power delivery, and a durable bottom end that can handle the added stress. Proper installation and tuning are just as critical as the parts themselves, so investing in quality components and a knowledgeable engine builder pays dividends in both horsepower and long‑term engine health.